Restore Trees That Grow reverted commits

The following commits were reverted prior to the release of GHC 8.4.1,
because the time to derive Data instances was too long [1].

 438dd1cbba13d35f3452b4dcef3f94ce9a216905 Phab:D4147
 e3ec2e7ae94524ebd111963faf34b84d942265b4 Phab:D4177
 47ad6578ea460999b53eb4293c3a3b3017a56d65 Phab:D4186

The work is continuing, as the minimum bootstrap compiler is now
GHC 8.2.1, and this allows Plan B[2] for instances to be used.  This
will land in a following commit.

Updates Haddock submodule

[1] https://ghc.haskell.org/trac/ghc/wiki/ImplementingTreesThatGrow/Instances
[2] https://ghc.haskell.org/trac/ghc/wiki/ImplementingTreesThatGrow/Instances#PLANB

1 files changed, 45 insertions, 46 deletions

diff --git a/compiler/typecheck/TcRnTypes.hs b/compiler/typecheck/TcRnTypes.hs
index 6c221b75e8..f13726c56d 100644
--- a/compiler/typecheck/TcRnTypes.hs
+++ b/compiler/typecheck/TcRnTypes.hs
@@ -3475,58 +3475,57 @@ lexprCtOrigin :: LHsExpr GhcRn -> CtOrigin
 lexprCtOrigin (L _ e) = exprCtOrigin e
 
 exprCtOrigin :: HsExpr GhcRn -> CtOrigin
-exprCtOrigin (HsVar (L _ name)) = OccurrenceOf name
-exprCtOrigin (HsUnboundVar uv)  = UnboundOccurrenceOf (unboundVarOcc uv)
-exprCtOrigin (HsConLikeOut {})  = panic "exprCtOrigin HsConLikeOut"
-exprCtOrigin (HsRecFld f)       = OccurrenceOfRecSel (rdrNameAmbiguousFieldOcc f)
-exprCtOrigin (HsOverLabel _ l)  = OverLabelOrigin l
-exprCtOrigin (HsIPVar ip)       = IPOccOrigin ip
-exprCtOrigin (HsOverLit lit)    = LiteralOrigin lit
-exprCtOrigin (HsLit {})         = Shouldn'tHappenOrigin "concrete literal"
-exprCtOrigin (HsLam matches)    = matchesCtOrigin matches
-exprCtOrigin (HsLamCase ms)     = matchesCtOrigin ms
-exprCtOrigin (HsApp e1 _)       = lexprCtOrigin e1
-exprCtOrigin (HsAppType e1 _)   = lexprCtOrigin e1
-exprCtOrigin (HsAppTypeOut {})  = panic "exprCtOrigin HsAppTypeOut"
-exprCtOrigin (OpApp _ op _ _)   = lexprCtOrigin op
-exprCtOrigin (NegApp e _)       = lexprCtOrigin e
-exprCtOrigin (HsPar e)          = lexprCtOrigin e
-exprCtOrigin (SectionL _ _)     = SectionOrigin
-exprCtOrigin (SectionR _ _)     = SectionOrigin
-exprCtOrigin (ExplicitTuple {}) = Shouldn'tHappenOrigin "explicit tuple"
-exprCtOrigin ExplicitSum{}      = Shouldn'tHappenOrigin "explicit sum"
-exprCtOrigin (HsCase _ matches) = matchesCtOrigin matches
-exprCtOrigin (HsIf (Just syn) _ _ _) = exprCtOrigin (syn_expr syn)
-exprCtOrigin (HsIf {})          = Shouldn'tHappenOrigin "if expression"
-exprCtOrigin (HsMultiIf _ rhs)  = lGRHSCtOrigin rhs
-exprCtOrigin (HsLet _ e)        = lexprCtOrigin e
-exprCtOrigin (HsDo _ _ _)       = DoOrigin
-exprCtOrigin (ExplicitList {})  = Shouldn'tHappenOrigin "list"
-exprCtOrigin (ExplicitPArr {})  = Shouldn'tHappenOrigin "parallel array"
-exprCtOrigin (RecordCon {})     = Shouldn'tHappenOrigin "record construction"
-exprCtOrigin (RecordUpd {})     = Shouldn'tHappenOrigin "record update"
-exprCtOrigin (ExprWithTySig {}) = ExprSigOrigin
-exprCtOrigin (ExprWithTySigOut {}) = panic "exprCtOrigin ExprWithTySigOut"
-exprCtOrigin (ArithSeq {})      = Shouldn'tHappenOrigin "arithmetic sequence"
-exprCtOrigin (PArrSeq {})       = Shouldn'tHappenOrigin "parallel array sequence"
-exprCtOrigin (HsSCC _ _ e)      = lexprCtOrigin e
-exprCtOrigin (HsCoreAnn _ _ e)  = lexprCtOrigin e
-exprCtOrigin (HsBracket {})     = Shouldn'tHappenOrigin "TH bracket"
+exprCtOrigin (HsVar _ (L _ name)) = OccurrenceOf name
+exprCtOrigin (HsUnboundVar _ uv)  = UnboundOccurrenceOf (unboundVarOcc uv)
+exprCtOrigin (HsConLikeOut {})    = panic "exprCtOrigin HsConLikeOut"
+exprCtOrigin (HsRecFld _ f)    = OccurrenceOfRecSel (rdrNameAmbiguousFieldOcc f)
+exprCtOrigin (HsOverLabel _ _ l)  = OverLabelOrigin l
+exprCtOrigin (HsIPVar _ ip)       = IPOccOrigin ip
+exprCtOrigin (HsOverLit _ lit)    = LiteralOrigin lit
+exprCtOrigin (HsLit {})           = Shouldn'tHappenOrigin "concrete literal"
+exprCtOrigin (HsLam _ matches)    = matchesCtOrigin matches
+exprCtOrigin (HsLamCase _ ms)     = matchesCtOrigin ms
+exprCtOrigin (HsApp _ e1 _)       = lexprCtOrigin e1
+exprCtOrigin (HsAppType _ e1)     = lexprCtOrigin e1
+exprCtOrigin (OpApp _ _ op _)     = lexprCtOrigin op
+exprCtOrigin (NegApp _ e _)       = lexprCtOrigin e
+exprCtOrigin (HsPar _ e)          = lexprCtOrigin e
+exprCtOrigin (SectionL _ _ _)     = SectionOrigin
+exprCtOrigin (SectionR _ _ _)     = SectionOrigin
+exprCtOrigin (ExplicitTuple {})   = Shouldn'tHappenOrigin "explicit tuple"
+exprCtOrigin ExplicitSum{}        = Shouldn'tHappenOrigin "explicit sum"
+exprCtOrigin (HsCase _ _ matches) = matchesCtOrigin matches
+exprCtOrigin (HsIf _ (Just syn) _ _ _) = exprCtOrigin (syn_expr syn)
+exprCtOrigin (HsIf {})           = Shouldn'tHappenOrigin "if expression"
+exprCtOrigin (HsMultiIf _ rhs)   = lGRHSCtOrigin rhs
+exprCtOrigin (HsLet _ _ e)       = lexprCtOrigin e
+exprCtOrigin (HsDo {})           = DoOrigin
+exprCtOrigin (ExplicitList {})   = Shouldn'tHappenOrigin "list"
+exprCtOrigin (ExplicitPArr {})   = Shouldn'tHappenOrigin "parallel array"
+exprCtOrigin (RecordCon {})      = Shouldn'tHappenOrigin "record construction"
+exprCtOrigin (RecordUpd {})      = Shouldn'tHappenOrigin "record update"
+exprCtOrigin (ExprWithTySig {})  = ExprSigOrigin
+exprCtOrigin (ArithSeq {})       = Shouldn'tHappenOrigin "arithmetic sequence"
+exprCtOrigin (PArrSeq {})      = Shouldn'tHappenOrigin "parallel array sequence"
+exprCtOrigin (HsSCC _ _ _ e)     = lexprCtOrigin e
+exprCtOrigin (HsCoreAnn _ _ _ e) = lexprCtOrigin e
+exprCtOrigin (HsBracket {})      = Shouldn'tHappenOrigin "TH bracket"
 exprCtOrigin (HsRnBracketOut {})= Shouldn'tHappenOrigin "HsRnBracketOut"
 exprCtOrigin (HsTcBracketOut {})= panic "exprCtOrigin HsTcBracketOut"
-exprCtOrigin (HsSpliceE {})     = Shouldn'tHappenOrigin "TH splice"
-exprCtOrigin (HsProc {})        = Shouldn'tHappenOrigin "proc"
-exprCtOrigin (HsStatic {})      = Shouldn'tHappenOrigin "static expression"
-exprCtOrigin (HsArrApp {})      = panic "exprCtOrigin HsArrApp"
-exprCtOrigin (HsArrForm {})     = panic "exprCtOrigin HsArrForm"
-exprCtOrigin (HsTick _ e)       = lexprCtOrigin e
-exprCtOrigin (HsBinTick _ _ e)  = lexprCtOrigin e
-exprCtOrigin (HsTickPragma _ _ _ e) = lexprCtOrigin e
-exprCtOrigin EWildPat           = panic "exprCtOrigin EWildPat"
+exprCtOrigin (HsSpliceE {})      = Shouldn'tHappenOrigin "TH splice"
+exprCtOrigin (HsProc {})         = Shouldn'tHappenOrigin "proc"
+exprCtOrigin (HsStatic {})       = Shouldn'tHappenOrigin "static expression"
+exprCtOrigin (HsArrApp {})       = panic "exprCtOrigin HsArrApp"
+exprCtOrigin (HsArrForm {})      = panic "exprCtOrigin HsArrForm"
+exprCtOrigin (HsTick _ _ e)           = lexprCtOrigin e
+exprCtOrigin (HsBinTick _ _ _ e)      = lexprCtOrigin e
+exprCtOrigin (HsTickPragma _ _ _ _ e) = lexprCtOrigin e
+exprCtOrigin (EWildPat {})      = panic "exprCtOrigin EWildPat"
 exprCtOrigin (EAsPat {})        = panic "exprCtOrigin EAsPat"
 exprCtOrigin (EViewPat {})      = panic "exprCtOrigin EViewPat"
 exprCtOrigin (ELazyPat {})      = panic "exprCtOrigin ELazyPat"
 exprCtOrigin (HsWrap {})        = panic "exprCtOrigin HsWrap"
+exprCtOrigin (XExpr {})         = panic "exprCtOrigin XExpr"
 
 -- | Extract a suitable CtOrigin from a MatchGroup
 matchesCtOrigin :: MatchGroup GhcRn (LHsExpr GhcRn) -> CtOrigin